Turtles all the way down

I visited a lovely nearby cafe this Sunday which serves amazing waffles alongside a selection of books you can read while enjoying your food. As I picked up ‘A Brief History of Time’ by Stephen Hawking, I was greeted by one of the best introductory pages ever written for a book (at least for me).

As much as I would love to explain it, there is no way I can do justice to it over what he wrote, so here is the excerpt from the book:

A well-known scientist (some say it was Bertrand Russell) once gave a public lecture on astronomy. He described how the earth orbits around the sun and how the sun, in turn, orbits around the center of a vast collection of stars called our galaxy. At the end of the lecture, a little old lady at the back of the room got up and said: “What you have told us is rubbish. The world is really a flat plate supported on the back of a giant tortoise.” The scientist gave a superior smile before replying, “What is the tortoise standing on.” “You’re very clever, young man, very clever,” said the old lady. “But it’s turtles all the way down!”

Most people would find the picture of our universe as an infinite tower of tortoises rather ridiculous, but why do we think we know better? What do we know about the universe, and how do we know it? Where did the universe come from, and where is it going? Did the universe have a beginning, and if so, what happened before then? What is the nature of time? Will it ever come to an end? Can we go back in time? Recent breakthroughs in physics, made possible in part by fantastic new technologies, suggest answers to some of these longstanding questions. Someday these answers may seem as obvious to us as the earth orbiting the sun – or perhaps as ridiculous as a tower of tortoises. Only time (whatever that may be) will tell.

The last line, that casts a doubt on all our known realities, means so much. We think what we know is absolute, but what does that even mean? Even the way we perceive quantities is relative in nature. While every generation, since time immemorial, has believed their times to be the best in human history, it is quite humbling to cast our current beliefs in the same shadow of doubt that we use for everything that came before it.

What if we are right? Time will tell. What if we are wrong? Time will tell.